Abstract: Methods and systems are disclosed wherein TCP may approximate Reliable Transport Protocol (RTP) or UDP delivery for real-time video/data conferencing applications that have long RTT connections.

Abstract: Doppler correlators are configured to receive samples of a signal sampled based on a frequency. Each Doppler correlator includes successive butterfly elements. Each butterfly element includes cross-coupled first and second branches that include a sample delay that doubles for each successive butterfly element, and a sample inversion selectively placed in one of the first and second branches to encode into the successive butterfly elements of each Doppler correlator the same code sequence. Each Doppler correlator is configured with a respective phase rotation that varies across the Doppler correlators.

Abstract: In a transmit method, a set of data eigenvectors that are based on a Prometheus Orthonormal Set (PONS) code construction and orthogonal to each other are stored, wherein the data eigenvectors are mapped to unique multi-bit words. A pilot sequence representing a pilot eigenvector that is based on the PONS code construction and orthogonal to each of the data eigenvectors is generated. Input data are grouped into multi-bit words and data eigenvectors among the data eigenvectors are selected based on the multi-bit words. A spread data sequence including the selected data eigenvectors and that is synchronized to the pilot sequence is generated. An acoustic signal including the synchronized pilot sequence and the spread data sequence is generated. The acoustic signal is transmitted.

Abstract: Time-offset, time-overlapping signals are received. The signals each include a pilot code, and at least some of the signals each include a user code occupying a time slot time-synchronized to a respective pilot code. Time-offset cross-correlation peaks for respective ones of the pilot codes are generated, each cross-correlation peak indicating a respective one of the time slots. For each time slot a respective projection vector including user code projections each indicative of whether a respective user code of known user codes is present in the time slot is generated. Particular ones of the projection vectors are selectively combined into an aggregate projection vector of aggregate user code projections, such that the aggregate projection vector has a signal-to-noise ratio (SNR) greater than the projection vectors individually. The user code is selected from among the known user codes based on the aggregate user code projections of the aggregate projection vector.

Abstract: An endpoint device receives a sequence of audio frames. The endpoint device determines for each audio frame a respective importance level among possible importance levels ranging from a low importance level to a high importance level based on content in the audio frame indicative of the respective importance level. The endpoint device associates each audio frame with the respective importance level, to produce different subsets of audio frames associated with respective ones of different importance levels. The endpoint device, for each subset of audio frames, applies forward error correction to a fraction of audio frames in the subset of audio frames, wherein the fraction increases as the importance level of the audio frames in the subset increases, and does not apply forward error correction to remaining audio frames in the subset.

Abstract: Presented herein are downstream recovery (error correction) techniques for an aggregated/consolidated media stream. In one example, a consolidated media stream that includes source media packets from one or more sources is sent to one or more downstream receiving devices. Based on the source media packets, one or more self-describing recovery packets for downstream error correction of the source media packets are generated. The self-describing recovery packets include a mapping to the source media packets used to generate the self-describing recovery packets, thereby avoiding the addition of error correction information in the consolidated media stream. The one or more self-describing recovery packets are sent to each of the downstream receiving devices as a separate stream.

Abstract: An access server communicates with a video conference device and a user device. The access server and the user device may access known mappings, including a default mapping. Each mapping is configured to map between tokens and symbols according to a distinct mapping relationship between the multi-bit tokens and the symbols. The access server instructs the video conference device to map an initial token to an initial symbol based on the default mapping and to transmit the initial symbol. The access server receives from the user device the initial token and a challenge mapping selected by the user device. The access server determines a challenge token that the challenge mapping maps to a challenge symbol, and instructs the video conference device to transmit the challenge symbol. The access server grants the user device access to an information carrying channel only if the challenge token is received from the user device.

Abstract: A first endpoint generates an acoustic spread spectrum signal including a pilot sequence and a data sequence representing a token synchronized to the pilot sequence, transmits the acoustic spread spectrum signal, and records a transmit time at which the acoustic spread spectrum signal is transmitted. A receive time at which a second endpoint received the acoustic spread spectrum signal transmitted by the first endpoint is received from the second endpoint along with an indication of a second token as recovered from the received acoustic spread spectrum signal by the second endpoint. A separation distance between the first endpoint and the second endpoint is computed based on a time difference between the transmit time and the receive time. The first endpoint is paired with the second endpoint when the token matches the second token and the computed distance is less than a threshold distance.

Abstract: An endpoint device receives a sequence of audio frames. The endpoint device determines for each audio frame a respective importance level among possible importance levels ranging from a low importance level to a high importance level based on content in the audio frame indicative of the respective importance level. The endpoint device associates each audio frame with the respective importance level, to produce different subsets of audio frames associated with respective ones of different importance levels. The endpoint device, for each subset of audio frames, applies forward error correction to a fraction of audio frames in the subset of audio frames, wherein the fraction increases as the importance level of the audio frames in the subset increases, and does not apply forward error correction to remaining audio frames in the subset.

Abstract: In a transmit method, a set of data eigenvectors that are based on a Prometheus Orthonormal Set (PONS) code construction and orthogonal to each other are stored, wherein the data eigenvectors are mapped to unique multi-bit words. A pilot sequence representing a pilot eigenvector that is based on the PONS code construction and orthogonal to each of the data eigenvectors is generated. Input data are grouped into multi-bit words and data eigenvectors among the data eigenvectors are selected based on the multi-bit words. A spread data sequence including the selected data eigenvectors and that is synchronized to the pilot sequence is generated. An acoustic signal including the synchronized pilot sequence and the spread data sequence is generated. The acoustic signal is transmitted.

Abstract: In a transmit method, a set of data eigenvectors that are based on a Prometheus Orthonormal Set (PONS) code construction and orthogonal to each other are stored, wherein each of the data eigenvectors is mapped to a unique multi-bit word. A pilot sequence representing a pilot eigenvector that is based on the PONS code construction and orthogonal to each of the data eigenvectors is generated. Input data is grouped into multi-bit words and ones of the data eigenvectors mapped to the multi-bit words are selected. A spread data sequence including the selected ones of the data eigenvectors and that is synchronized to the pilot sequence is generated. An acoustic signal including the synchronized pilot sequence and the spread data sequence is generated. The acoustic signal is transmitted.

Abstract: Large source data packets having large packet sizes and small source data packets having small packet sizes that are smaller than the large packet sizes are received. The small source data packets and the large source data packets are sent to a receiving device without forward error correction (FEC). The small source data packets are aggregated into a container packet having a header configured to differentiate the container packet from the large source data packets and the small source data packets. The large source data packets and the container packet are encoded with forward error correction to produce FEC-encoded packets to enable forward error correction of the large source data packets and the container packet at the receiving device. The FEC-encoded packets are sent to the receiving device.

Abstract: In a transmit method, a set of data eigenvectors that are based on a Prometheus Orthonormal Set (PONS) code construction and orthogonal to each other are stored, wherein each of the data eigenvectors is mapped to a unique multi-bit word. A pilot sequence representing a pilot eigenvector that is based on the PONS code construction and orthogonal to each of the data eigenvectors is generated. Input data is grouped into multi-bit words and ones of the data eigenvectors mapped to the multi-bit words are selected. A spread data sequence including the selected ones of the data eigenvectors and that is synchronized to the pilot sequence is generated. An acoustic signal including the synchronized pilot sequence and the spread data sequence is generated. The acoustic signal is transmitted.

Abstract: A method is described and in one embodiment includes receiving at a first node in a communications network a message associated with a first flow, wherein the message comprises a flow treatment attribute including metadata indicative of how the first flow should be treated in the network; analyzing the flow treatment attribute at the first node; setting policy for treatment of the flow in the network based on the analyzing; and forwarding the message to a next network node.

Abstract: Embodiments include detecting an increase in delay of a flow assigned to a first queue of a network device, where the increase is sufficient to cause the flow rate of the flow to decrease if the flow is delay-sensitive. Embodiments further include determining whether an amount of bandwidth consumed by the flow decreases sufficiently after the increase is detected, and assigning the flow to a second queue based, at least in part, on determining the amount of bandwidth consumed by the flow does not decrease sufficiently. Specific embodiments include evaluating a series of two or more bandwidth measurements of the flow according to a bandwidth reduction measure to determine whether the amount of bandwidth consumed by the flow decreases by sufficiently. More specific embodiments include the first queue being configured to receive delay-sensitive flows and the second queue being configured to receive delay-insensitive nice flows.

Abstract: An access server communicates with a video conference device and a user device. The access server and the user device may access known mappings, including a default mapping. Each mapping is configured to map between tokens and symbols according to a distinct mapping relationship between the multi-bit tokens and the symbols. The access server instructs the video conference device to map an initial token to an initial symbol based on the default mapping and to transmit the initial symbol. The access server receives from the user device the initial token and a challenge mapping selected by the user device. The access server determines a challenge token that the challenge mapping maps to a challenge symbol, and instructs the video conference device to transmit the challenge symbol. The access server grants the user device access to an information carrying channel only if the challenge token is received from the user device.

Abstract: Large source data packets having large packet sizes and small source data packets having small packet sizes that are smaller than the large packet sizes are received. The small source data packets and the large source data packets are sent to a receiving device without forward error correction (FEC). The small source data packets are aggregated into a container packet having a header configured to differentiate the container packet from the large source data packets and the small source data packets. The large source data packets and the container packet are encoded with forward error correction to produce FEC-encoded packets to enable forward error correction of the large source data packets and the container packet at the receiving device. The FEC-encoded packets are sent to the receiving device.

Abstract: A method that includes: (1) transmitting, at a first transmit time point, a first probe packet over a network connection to a conferencing server immediately before transmitting a data packet, the first probe packet arriving at the conferencing server at a first receive time point; (2) transmitting, at a second transmit time point, a second probe packet over the network connection to the conferencing server immediately after transmitting the data packet, the second probe packet arriving at the conferencing server at a second receive time point, the first and second probe packets being smaller than the data packet; (3) receiving information encoding a first difference between the first and second transmit time points and a second difference between the first and second receive time points; and (4) based on the first and second differences, modifying a transmission parameter associated with data packets to be transmitted thereafter to the conferencing server.

Abstract: Presented herein are downstream recovery (error correction) techniques for an aggregated/consolidated media stream. In one example, a consolidated media stream that includes source media packets from one or more sources is sent to one or more downstream receiving devices. Based on the source media packets, one or more self-describing recovery packets for downstream error correction of the source media packets are generated. The self-describing recovery packets include a mapping to the source media packets used to generate the self-describing recovery packets, thereby avoiding the addition of error correction information in the consolidated media stream. The one or more self-describing recovery packets are sent to each of the downstream receiving devices as a separate stream.

Abstract: A communication device detects sound with a microphone to produce a sound signal representative of the sound and searches the sound signal for unique inaudible sound signatures associated with a group identifier. Each sound signature identifies a respective communication device. Each sound signature is in an audible frequency band but masked to be imperceptible. If any of the sound signatures are determined to be present in the sound signal, the communication device selects one based on predetermined criteria associated with the group identifier.